The Hauck Open N Stop can be used for doors and stairs with a width from 75 to 80 cm. If you want to secure larger openings, we recommend the Open N Stop inclusive 9 cm extension (84 - 89 cm) or the Open N Stop inclusive 21 cm extension (96 - 101 cm). All models of this gate can be extended with a second extension up to 122 cm and with Y-spindles to be used for round stair railings.Assembly is quick and easy. The metal gate is clamped between walls or in door frames with four fixing screws. No drilling required.*Open’n Stop has a double manual locking mechanism. It can be opened with just one hand and engages reliably into the childproof lock.With separately available extensions, the gate can be individually extended and used as a stair gate. And if you have a stair railing with round bars, you can attach the safety gate next to the extensions of 9 and 21 cm with the separately available Y-spindles.Opening dimensions with extensions:75 - 80 cm = gate without extensions96 - 101 cm